β-Blockers (timolol maleate, carteolol, etc.), prostaglandin type compounds (isopropyl unoprostone and latanoprost) and a carbonic anhydrase inhibitor (dorzolamide hydrochloride) have been mainly used as agents for the treatment of glaucoma. Moreover, an α1-blocker (bunazosin hydrochloride) and an αβ-blocker (nipradilol) are now at the stage of clinical trials or application for approval.
There are reports (for example, EP795326, EP631780, WO95/21609, WO91/15206, etc.) that angiotensin II antagonists are useful agents for the treatment of glaucoma. Among angiotensin II antagonists, only CGP-48933 has been subjected to clinical trial. It was reported that its effect for glaucoma was insufficient (Eur. J. Ophthalmol. 1997, January-March; 7(1): 35-9) and the development of it has been stopped since then.